Laser diodes emit light when current is passed through the diode. The output radiance of the laser diode varies as the drive current through the diode is varied. The output radiance of the laser diode also varies as the temperature of the diode varies. This can be problematic in part because the temperature of a laser diode may be affected by the historical drive current. This “self heating” causes the output radiance to vary not only as a function of the drive current through the laser diode, but also as a function of historical drive current.